J Genet Med.  2015 Jun;12(1):38-43. 10.5734/JGM.2015.12.1.38.

Analysis of trinucleotide repetitive sequences for Korean patients with spinocerebellar ataxia types 8, 12, and 17

• Kim GH
• Chung SJ
• Ryu HS
• Kim J
• Lee JJ
• Choi SH
• Lee J
• Lee BH
• Choi JH
• Yoo HW

• KMID: 2055588
• DOI: http://doi.org/10.5734/JGM.2015.12.1.38

Abstract

PURPOSE
Spinocerebellar ataxias (SCAs) are progressive neurodegenerative disorders with diverse modes of inheritance. There are several subtypes of SCAs. SCA 8, SCA 12, and SCA 17 are the less common forms of SCAs with limited information available on their epidemiological profiles in Korea. The purpose of this study was to investigate the prevalence of SCA8, SCA12, and SCA17 in Korea.
MATERIALS AND METHODS
Ninety-six unrelated Korean patients were enrolled and showed normal trinucleotide repeats through polymerase-chain reaction (PCR) for the genes ATXN1, ATXN2, ATXN3, CACNA1A , and ATXN7, which correspond to SCA1, SCA2, SCA3, SCA6, and SCA7, respectively. PCR products from patients were further analyzed by capillary electrophoresis using fluorescence labeled primers for the genes ATXN8OS, PPP2R2B, and TBP, which correspond to SCA8, SCA12, and SCA17.
RESULTS
Three patients had 104, 97, and 75 abnormal expanded repeats in the ATXN8OS gene, the causative gene for SCA8. None of the patients exhibited abnormal repeats in SCA12 and SCA17. Normal trinucleotide repeat ranges of the cohort in this study were estimated to be 17-34 copies (average, 24+/-4 copies) for SCA8, 7-18 copies (average, 13+/-3 copies) for SCA12, and 26-43 copies (average, 35+/-2 copies) for SCA17.
CONCLUSION
This study demonstrated that SCA8, SCA12, and SCA17 are rare in Korean patients with SCA, and further genetic studies are warranted to enhance the mutation detection rate in the Korean SCA population.

Keyword

Spinocerebellar ataxia; Spinocerebellar ataxia 8; Koreans

MeSH Terms

Asian Continental Ancestry Group
Cohort Studies
Electrophoresis, Capillary
Fluorescence
Humans
Korea
Neurodegenerative Diseases
Polymerase Chain Reaction
Prevalence
Repetitive Sequences, Nucleic Acid*
Spinocerebellar Ataxias*
Trinucleotide Repeats
Wills